Oil or fat composition

ABSTRACT

There is provided an oil or fat composition composed chiefly of triglycerides wherein the amount of medium-chain fatty acids in all the fatty acids composing the oil or fat composition is 5 to 23% by mass and the amount of triglycerides having two medium-chain fatty acid residues in the molecule in all the triglycerides is 1 to 20% by mass. 
     The oil or fat composition is low in body fat accumulation, has equal cooking properties with conventional edible oils and has good flavor and high safety.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a division of U.S. Ser. No. 09/440,137, filed Nov.15, 1999, now U.S. Pat. No. 6,835,408.

FIELD OF THE INVENTION AND RELATED ART STATEMENT

This invention relates to an oil or fat composition for food. Morespecifically, it relates to an oil or fat composition which is lessaccumulated as body fat and is excellent in cooking properties andflavor as edible oil.

Obesity is a state of body fat being accumulated in excess, and it iswell known that many diseases including metabolic disorders such asdiabetes and hyperlipemia and diseases in circulatory organs such ashypertension and ischemic cardiac diseases tend to follow obesity.According to the results of the national nutrition investigation carriedout by the Japanese Welfare Ministry, one of seven adults is obese, andobesity is a close problem not only in Europe and America but also inJapan. Fat contained in meals is one of nutrients most profoundlyrelated to the accumulation of body fat, but the excessive ingestion offat may result in obesity. However, fat has intrinsic taste, and mealsof extremely reduced fat are often insufficient to give satisfaction.Further, when deep-fried food or fried food is made, an edible oil isindispensable as a heating medium.

For resolving such situation, so-called fat substitutes have beendeveloped. However, none of them are fully satisfactory in safety,physical properties, cooking properties and flavor. For example, it isdisclosed that sucrose fatty acid esters are not absorbed in thedigestive tract and excreted into the feces, and can be used as a lowcalorie oil (U.S. Pat. No. 3,600,186). In the United States of America,sucrose fatty acid esters are permitted to be used for salty snackconfectionery, and potato chips in use of them are already put on themarket, but the indication of “There is a possibility that abdominalconvulsions or loose passages are caused” and “The absorption of fatsoluble vitamins is inhibited” is compulsory for commodities in use ofsucrose fatty acid esters. The energy density of protein orcarbohydrates is half or less that of fat. Thus, it is known that byprocessing protein or carbohydrates so that fat-like physical propertiesor flavor may come out, low calorie fat substitutes can be provided(Eiyogaku Review (Dietetics Review), volume 4, No. 4, pages 23-33,1996). It is possible to make low calorie ice creams, bakery products,cakes by using such fat substitutes. However, they have thedisadvantages that they are poor in resistance to heat and cannot beused as heating media for deep-frying or frying.

In Japanese Laid-open Patent Publication (Tokuhyohei) No. 501812/1992,it is disclosed that a low calorie oil or fat can be provided usingtriglycerides composed of long-chain fatty acids and short-chain fattyacids. However, triglycerides composed of short-chain fatty acids havepeculiar odor, and are not suitable as general purpose edible oilsbecause foodstuffs to be cooked using them are limited. Further,middle-chain fatty acids are known to be lower in body fat accumulationbecause they are more easily to be converted into energy (J. Lipid Res.37, 708-726 (1996)). However, although triglycerides composed ofmiddle-chain fatty acids are intrinsically high in safety, it isreported that if a large amount of them are intaked, symptoms such asdiarrhea, nausea, stomachaches, heartburn and anorexia are caused. Oilor fat compositions containing diglycerides as effective components andbeing lower in body fat accumulation are disclosed in Japanese Laid-openPatent Publication Nos. 300826/1992, 60180/1996 and 176181/1998.However, the safety of oil or fat compositions abundantly containingdiglycerides is not completely proved. Moreover, it is difficult toproduce diglycerides in high concentration at low costs, and such oil orfat compositions have the disadvantage that they are hard to use forgeneral purposes from the economical viewpoint. In Japanese Laid-openPatent Publication No. 269478/1996 is disclosed an oil or fatcomposition composed of diglycerides and triglycerides, which containstriglycerides having two middle-chain fatty acid residues in themolecule in an amount of 31% by mass or more and is less in body fataccumulation. However, this invention has the same problem as in theabove Japanese Laid-open Patent Publication Nos. 300826/1992, 60180/1996and 176181/1998 because diglycerides are also used as effectivecomponents. Further, the composition hap the disadvantages that since alarge amount of medium-chain fatty acids are contained, its smoke pointis low and there is striking foaming, and thus it is not suitable forfrying (deep frying or frying) cooking.

OBJECT AND SUMMARY OF THE INVENTION

The object of the invention lies in providing an oil or fat compositionwhich is low in body fat accumulation, has equal cooking properties withconventional edible oils and has good flavor and high safety.

In order to attain the above object, the present inventors have madesequential researches, and as a result they have found that theproportion of middle-chain fatty acid residues in all the fatty acidresidues and the proportion of triglycerides having two middle-chainfatty acid residues in all the triglycerides are closely related withthe degree of body fat accumulation, and have completed this invention.

Thus the invention relates to an oil or fat composition being low inbody fat accumulation, composed chiefly of triglycerides wherein theproportion of middle-chain fatty acids in all the fatty acids composingthe oil or fat composition is 5 to 23% by mass and the proportion oftriglycerides having two middle-chain fatty acid residues in themolecule in all the triglycerides is 1 to 20% by mass. The middle-chainfatty acids are preferably saturated fatty acids having 6 to 12carbon-atoms. Further, it is preferred that the proportion oftriglycerides having three middle-chain fatty acid residues in themolecule in all the triglycerides composing the oil or fat compositionis 3% by mass or less. The proportion of long-chain saturated fattyacids in all the long-chain fatty acids composing the oil or fatcomposition is 20% by mass or less. When emulsifiers, especiallyemulsifiers in specific combinations are incorporated into the oil orfat composition, frying (deep frying and frying) properties,particularly antifoaming can further be enhanced.

The invention also relates to an oil or fat composition for cookingbeing low in body fat accumulation and having equal cooking propertiesand stability in storage with conventional edible oil, which comprisessuch an oil or fat composition and conventional additives for oil or fatcompositions for cooking.

DETAILED DESCRIPTION OF THE INVENTION

In the invention, when the term “frying” is used alone, it is assumed toinclude both deep frying and frying. This is also applied when a likeword such as “fried” is used alone.

The oil or fat composition of the invention chiefly comprisestriglycerides. The term “chiefly” is assumed to mean that triglyceridesare contained in an amount of 85% by mass or more, preferably 95% bymass or more in the oil or fat composition.

The middle-chain fatty acids in the invention are assumed to mean fattyacids, particularly saturated fatty acids, having 6 to 12 carbon atoms.As examples, there can be mentioned caproic acid, caprylic acid, capricacid and lauric acid, and saturated fatty acids having 8 to 10 carbonatoms, particularly caprylic acid and capric acid are preferred. Thelong-chain fatty acids in the invention are assumed to mean saturated orunsaturated fatty acids having 14 or more, preferably 14 to 22 carbonatoms. As the long-chain fatty acids, there can be mentioned thosehaving 14 or more, preferably 14 to 22 carbon atoms, for example,long-chain saturated fatty acids such as myristic acid, palmitic acid,stearic acid, arachidic acid, behenic acid, lignoceric acid and ceroticacid, and long-chain unsaturated fatty acids such as myristoleic acid,pentadecenoic acid, palmitoleic acid, hexadecatrienoic acid,heptadecenoic acid, oleic acid, linolic acid, α-linolenic acid,γ-linolenic acid, octadecatetraenoic acid, icosenoic acid, icosadienoicacid, icosatrienoic acid, icosatetraenoic acid, arachidonic acid,icosapentaenoic acid, docosenoic acid, docosadienoic acid,docosapentaenoic acid and docosahexaenoic acid. A fatty acid residue isa group obtained by removing the OH of the carboxyl group from a fattyacid.

In the oil or fat composition of the invention, it is necessary that theproportion of middle-chain fatty acids in all the fatty acids composingthe oil or fat composition is 5 to 23% by mass and the proportion oftriglycerides having two middle-chain fatty acid residues in themolecule in all the triglycerides is 1 to 20% by mass. Beyond thesescopes, the merit of low body fat accumulation cannot be obtained. Theproportion of middle-chain fatty acids is preferably 6 to 23% by mass,and the proportion of the triglycerides is preferably 3 to 20% by mass.

Further, the proportion of triglycerides having three middle—chain fattyacid residues in the molecule in all the triglycerides composing the oilor fat composition is preferably 3% by mass or less, more preferably 2%by mass or less, still more preferably 1% by mass or less. If theproportion is more than 3% by mass, smoking and foaming increase at thetime of cooking, and the oil or fat composition is not suitable as a oilor fat for frying. If the proportion is 1% by mass or less, remarkableimprovement is observed in smoking and foaming.

Further, the proportion of long-chain saturated fatty acids in all thelong-chain fatty acids composing the oil or fat composition ispreferably 20% by mass or less, more preferably 15% by mass or less,still more preferably 7% by mass or less. If the proportion is more than20% by mass, stability at low temperatures is lowered, crystallizationof oil or fat comes to occur in the oil or fat composition, and itusually becomes unfit for eating without heating.

The oil or fat composition of the invention being low in body fataccumulation can be obtained by suitably mixing oil or fat andmedium-chain fatty acids as raw materials, carrying outtransesterification reaction either using sodium methylate as a catalystor in the presence of a lipolytic enzyme, and, at that time, adjustingthe transesterification reaction so that the proportion of middle-chainfatty acids in all the fatty acids composing the oil or fat compositionand the proportion of triglycerides having two middle-chain fatty acidresidues in the molecule in all the triglycerides may fall within theabove specific ranges.

In the transesterification reaction, in addition to, the aboveadjustment, by adjusting the proportion of triglycerides having threemiddle-chain fatty acid residues in the molecule in all thetriglycerides composing the oil or fat composition, and/or theproportion of long-chain saturated fatty acids in all the long-chainfatty acids composing the oil or fat composition so that theseproportions may be in the above specific ranges, there can be obtainedan oil or fat composition which is low in body fat accumulation, and hasreduced smoking and foaming at the time of frying, and/or is excellentin stability at low temperatures.

As the raw material oil or fat, there can be mentioned conventionaledible oil or fat, for example, soybean oil, rapeseed oil, rapeseed oilcontaining oleic acid in a high concentration, corn oil, sesame oil,sesame salad oil, beafsteak plant oil, linseed oil, peanut oil,safflower oil, safflower oil containing oleic acid in a highconcentration, sunflower seed oil, sunflower seed oil containing oleicacid in a high concentration, cotton seed oil, grape seed oil, macadamianut oil, hazel nut oil, pumpkinseed oil, walnut oil, camellia oil, teaseed oil, perilla oil, borage oil, olive oil, rice bran oil, wheat germoil, palm oil, palm kernel oil, coconut oil, cacao butter, tallow, lard,chicken fat, cream, fish oil, seal oil, seaweed oil, and these oils orfats having reduced their saturation by breed improvement, these oils orfats having hydrogenated, oils or fats obtained from these oils or fatsby fractionation, etc.

Although some description was made about the medium-chain fatty acids,medium-chain fatty acid triglycerides can also be used either in placeof or together with the medium-chain fatty acids. As the medium-chainfatty acid triglycerides, there can be used triglycerides obtained bysubjecting medium-chain fatty acids and glycerol to esterificationreaction according to a conventional method, but there can preferably beused single acid triglycerides or mixed acid triglycerides composed ofsaturated fatty acids having 8 to 10 carbon atoms such as fatty acidsobtained by hydrolysis of coconut oil, generally called MCT (MediumChain Triglycerides), for example triglycerides of caprylic acid/capricacid=60/40-75/25 (mass ratio).

The proportion of middle-chain fatty acids in all the fatty acidscomposing the oil or fat composition, the proportion of triglycerideshaving two middle-chain fatty acid residues in the molecule in all thetriglycerides, and, if necessary, the proportion of triglycerides havingthree middle-chain fatty acid residues in the molecule in all thetriglycerides composing the oil or fat composition, and, if necessary,the proportion of long-chain saturated fatty acids in all the long-chainfatty acids composing the oil or fat composition can be adjusted bytaking the composition of the raw material oil or fat into account,adjusting the use ratio between the raw material oil or fat and themedium-chain fatty acids and measuring the reaction product during thetransesterification reaction for triglyceride composition.

When the transesterification reaction is carried out using sodiummethylate as a catalyst, a raw material oil or fat is mixed withmedium-chain fatty acid triglycerides at a mass ratio (the former/thelatter) of 71/29-97/3, and the mixture is heated to 80 to 120° C. undera reduced pressure of 100 mmHg or less to remove gaseous components andwater contained in the raw material mixture. Transesterificationreaction is carried out by adding sodium methylate thereto at an amountof 0.02 to 0.5% by mass and stirring the mixture at 80 to 120° C. for 10to 60 minutes either under normal pressure and a nitrogen gas stream orunder a reduced pressure of 10 mm Hg or less. The completion of thereaction is confirmed by measuring the reaction mixture for triglyceridecomposition using gas chromatography. The cessation of the reaction ismade by adding water or an acid such as phosphoric acid to the reactionproduct. Then, sufficient washing by water is made to remove thecatalyst and the excess acid, and, after drying, the reaction product isdecolored and deodorized by conventional methods.

When the transesterification is carried out using a lipolytic enzyme, araw material oil or fat is mixed with medium-chain fatty acids ormedium-chain fatty acid triglycerides at a mass ratio (the former/thelatter) of 71/29-97/3, and the mixture is adjusted to temperature in therange of 40 to 100° C., which is enough to exert the activity of thelipolytic enzyme. A lipolytic enzyme is added thereto in an amount of0.005 to 10% by mass based on the raw material mixture, andtransesterification reaction is carried out for 2 to 48 hours. Thisreaction is preferably carried out under normal pressure in a stream ofnitrogen. The completion of the reaction is confirmed by measuring thereaction mixture for triglyceride composition using gas chromatography.The cessation of the reaction is carried out by removing the enzyme byfiltration. The reaction product is washed by water, dried, and thendecolored and deodorized by conventional methods. When medium-chainfatty acids were used, the free fatty acids are removed, after thecessation of the reaction, by a film evaporator.

If the transesterification using the lipolytic enzyme is insufficient,the proportion of triglycerides having three middle-chain fatty acidresidues in the molecule becomes high. An oil or fat composition whichis high in the proportion of triglycerides having three middle-chainfatty acid residues in the molecule has the merit of being low in bodyfat accumulation, but is not preferred because of is intense smoking andfoaming at the time of continuous frying cooking.

As the lipolytic enzyme, there can be mentioned lipases derived from thegenus Alcaligenes, Candida, Rhizopus, Mucor or Pseudomonas andphospholipase A derived from liver, etc., but lipases derived from thegenus Candida or Rhizopus are particularly preferred.

The oil or fat composition of the invention can also be obtained byextraction from a plant such as soybean, rapeseed, corn, coconut, palm,olive, linseed, sunflower seed, safflower, camellia, cotton seed orcuphea which was improved for breeds so as to produce the oil or fatcomposition of the invention using the technique of geneticrecombination.

By incorporating emulsifiers into the oil or fat composition of theinvention, frying properties, particularly antifoaming can further beenhanced. As such emulsifiers, there can be mentioned sucrose fatty acidesters, polyglycerol fatty acid esters, succinic acid monoglycerides,monoglycerides, diglycerides, sorbitol fatty acid esters, sorbitan fattyacid esters, etc., and they can be used alone or in combination of twoor more kinds. The emulsifiers can be incorporated in an amount of 0.1to 6% by mass, preferably 0.3 to 5% by mass as a whole based on the oilor fat composition before the incorporation.

The sucrose fatty acid esters are esters between sucrose and saturatedor unsaturated fatty acids having 6 to 22 carbon atoms, and it ispreferred that the average substitution degree of all the hydroxylgroups is 37.5 to 87.5% and the proportion of polyesters not less thantriesters in all the sucrose fatty acid esters is 85% by mass or more.The polyglycerol fatty acid esters are esters between polyglycerol andsaturated or unsaturated fatty acids having 6 to 22 carbon atoms, and itis preferred that the average substitution degree of all the hydroxylgroups is 20 to 80%. The polyglycerol includes polyglycerols not lessthan triglycerides, preferably not more than decaglycerides. Themonoglycerides or diglycerides includes monoesters or diesters betweenglycerol or diglycerol and saturated or unsaturated fatty acids having 6to 22 carbon atoms, respectively, but the monoesters (monoglycerides)are preferred. As the succinic acid monoglycerides, there can preferablybe used succinic acid monoglycerides obtained by esterifyingmonoglycerides or diglycerides with succinic acid at a ratio (thelatter/the former) of 3:1 to 0.1:1. As the sorbitol fatty acid esters orsorbitan fatty acid esters, mono-to triesters between sorbitol orsorbitan and saturated or unsaturated fatty acids having 6 to 22 carbonatoms are preferred. In the above, as examples of the saturated orunsaturated fatty acids having 6 to 22 carbon atoms, there can bementioned those mentioned as examples of medium-chain fatty acids andlong-chain fatty acids.

As the combination of the emulsifiers, it is most preferred, for furtherenhancement of frying properties, particularly antifoaming, toincorporate 0.1 to 3% by mass at least one kind of sucrose fatty acidesters and polyglycerol fatty acid esters, 0.01 to 2% by mass succinicacid monoglycerides, and 0.1 to 3% by mass at least one kind ofmonoglycerides, diglycerides, sorbitol fatty acid esters and sorbitanfatty acid esters under the condition that the total amount of theemulsifiers is 0.3 to 5% by mass, based on the oil or fat composition ofthe invention before the incorporation.

The thus obtained oil or fat composition of the invention can be used,either as such or after incorporation of conventional additives for oilor fat compositions for cooking, as an oil or fat composition forcooking.

As such additives, there can be mentioned polyglycerol fatty acidesters, sucrose fatty acid esters, sorbitan fatty acid esters, vitaminE, ascorbic acid fatty acid esters, lignan, coenzyme Q, phospholipids,oryzanols, diglycerides, etc. for the purposes of enhancement ofstability in storage, enhancement of stability to oxidation, enhancementof stability to heat, inhibition of crystallization at low temperatures,etc., and vitamin E, ascorbic acid fatty acid esters, lignan, coenzymeQ, phospholipids, oryzanols, etc. in expectation for action to preventdiseases of adult people, action to prevent diseases from habits inlife, action to inhibit in vivo oxidation, and action to preventobesity.

The oil or fat composition for cooking of the invention has flavor equalto or more than that of edible oils on the market such as rapeseed oil,corn oil, safflower oil and soybean oil, and can be used not only forcooking such as frying, deep-frying or marinating, but also in foodscontaining oil or fat such as dressing, mayonnaise, margarine,confectionery, cake, beverages, etc. The characteristic of flavordiffers depending on the kinds of foods, but it is possible to makeplain foods wherein the tastes of the materials are kept alive. Further,the degree of sputtering of oil at the time of frying cooking is equalto or less than that of conventional edible oils. An action to lower theconcentration of lipids in the blood can also be expected bycontinuously taking a suitable amount of the oil or fat composition forcooking of the invention.

The invention is specifically described below according to examples, butit is not limited thereby.

EXAMPLE 1

Rapeseed oil (made by THE NISSHIN OIL MILLS, LTD.) (80 mass parts) and20 mass parts of MCT wherein the composing fatty acids are caprylicacid/capric acid=3/1 by mass ratio were mixed, and stirred at 120° C.under reduced pressure to carry out deaeration and dehydration. Sodiummethylate (0.1 mass part) was added thereto as a catalyst, and randomtransesterification reaction was carried out at 120° C. for 30 minutes.The reaction product was washed by water, dried, decolored anddeodorized by conventional methods to obtain Composition 1. ToComposition 1 were added 2.5% by mass sucrose fatty acid esters (made byMitsubishi Kagaku Foods Co., trade name: Ryoto-sugar ester O-170), 0.1%by mass succinic acid monoglycerides (made by Riken Vitamin Co., tradename: Poem B-10) and 1% by mass sorbitan fatty acid esters (made byRiken Vitamin Co., trade name: Poem O-80) to obtain Composition 2.Compositions 1 and 2 were measured for triglyceride composition andfatty acid composition by gas chromatography using column GS-1 andaccording to “Kijun Yushi Bunseki Shikenho (Standard Method forAnalyzing Oils and Fats) (1996)”, respectively (this is also the casewith the following examples and comparative examples). The results areshown in Table 1.

EXAMPLE 2

Lipase QL (made by Meito Sangyo Co., Ltd.)(0.1 mass part) was added tothe mixture of 85 mass parts of soybean salad oil (made by THE NISSHINOIL MILLS, LTD.) with 15 mass parts of MCT wherein the composing fattyacids are caprylic acid/capric acid=3/1 by mass ratio, andtransesterification reaction was carried out under stirring at 60° C.for 15 hours. The enzyme was filtered out from the reaction product, andthe filtrate was washed by water and dried, and then decolored anddeodorized to obtain Composition 3. The triglyceride composition and thefatty acid composition of Composition 3 are shown in Table 1.

EXAMPLE 3

After 77 mass parts of palm oil (made by THE NISSHIN OIL MILLS, LTD.)and 23 mass parts of a medium-chain fatty acid mixture of caprylicacid/capric acid 1/1 by mass ratio were mixed, 0.1 mass part of LipaseQL (made by Meito Sangyo Co., Ltd.) was added, and transesterificationreaction was carried out under stirring at 60° C. for 15 hours. Afterthe reaction, the enzyme was filtered out, free fatty acids in thefiltrate were removed by a film evaporator, and the filtrate wasdecolored and deodorized to obtain Composition 4. The triglyceridecomposition and the fatty acid composition of Composition 4 are shown inTable 1.

EXAMPLE 4

After 77 mass parts of corn oil (made by THE NISSHIN OIL MILLS, LTD.)and 23 mass parts of a medium-chain fatty acid mixture of caprylicacid/capric acid=1/1 by mass ratio were mixed, 0.1 mass part of LipaseQL (made by Meito Sangyo Co., Ltd.) was added, and transesterificationreaction was carried out under stirring at 60° C. for 15 hours. Afterthe reaction, the enzyme was filtered out, free fatty acids in thefiltrate were removed by a film evaporator, and the filtrate wasdecolored and deodorized to obtain Composition 5. The triglyceridecomposition and the fatty acid composition of Composition 5 are shown inTable 1.

EXAMPLE 5

Rapeseed oil (made by THE NISSHIN OIL MILLS, LTD.) (93 mass parts) and 7mass parts of MCT wherein the composing fatty acids are caprylicacid/capric acid=3/1 by mass ratio were mixed, and stirred at 120° C.under reduced pressure to carry out deaeration and dehydration. Sodiummethylate (0.1 mass part) was added thereto as a catalyst, and randomtransesterification reaction was carried out at 120° C. for 30 minutes.The reaction product was washed by water, dried, decolored anddeodorized by conventional methods to obtain Composition 6. Thetriglyceride composition and the fatty acid composition of Composition 6are shown in Table 2.

EXAMPLE 6

Rapeseed oil (made by THE NISSHIN OIL MILLS, LTD.) (90 mass parts) and10 mass parts of MCT wherein the composing fatty acids are caprylicacid/capric acid=3/1 by mass ratio were mixed, and stirred at 120° C.under reduced pressure to carry out deaeration and dehydration.

Sodium methylate (0.1 mass part) was added thereto as a catalyst, andrandom transesterification reaction was carried out at 120° C. for 30minutes. The reaction product was washed by water, dried, decolored anddeodorized by conventional methods to obtain Composition 7. Thetriglyceride composition and the fatty acid composition of Composition 7are shown in Table 2.

EXAMPLE 7

Lipase QL (made by Meito Sangyo Co., Ltd.)(0.1 mass part) was added tothe same mixture as in Example 2, and transesterification reaction wascarried out under stirring at 60° C. for 3 hours. The enzyme wasfiltered out from the reaction product, and the filtrate was washed bywater, dried, decolored and deodorized by conventional methods to obtainComposition 8. The triglyceride composition and the fatty acidcomposition of Composition 8 are shown in Table 2.

COMPARATIVE EXAMPLE 1

Rapeseed oil (made by THE NISSHIN OIL MILLS, LTD.) (75 mass parts) and25 mass parts of MCT wherein the composing fatty acids are caprylicacid/capric acid=3/1 by mass ratio were mixed, and stirred at 120° C.under reduced pressure to carry out deaeration and dehydration. Sodiummethylate (0.1 mass part) was added thereto as a catalyst, and randomtransesterification reaction was carried out at 120° C. for 30 minutes.The reaction product was washed by water, dried, decolored anddeodorized by conventional methods to obtain Composition 9. Thetriglyceride composition and the fatty acid composition of Composition 9are shown in Table 3.

COMPARATIVE EXAMPLE 2

Rapeseed oil (made by THE NISSHIN OIL MILLS, LTD.) (97 mass parts) and 3mass parts of MCT wherein the composing fatty acids are caprylicacid/capric acid=3/1 by mass ratio were mixed, and stirred at 120° C.under reduced pressure to carry out deaeration and dehydration. Sodiummethylate (0.1 mass part) was added thereto as a catalyst, and randomtransesterification reaction was carried out at 120° C. for 30 minutes.The reaction product was washed by water, dried, decolored anddeodorized by conventional methods to obtain Composition 10. Thetriglyceride composition and the fatty acid composition of Composition10 are shown in Table 3.

TABLE 1 Analytical values of oil or fat compositions (% by mass) ExampleComposi- Composi- Composi- Composi- Composi- tion 1 tion 2 tion 3 tion 4tion 5 Triglyceride composition 3M0L 1.5 1.5 tr. 2.0 1.9 2M1L 15.9 15.910.2 19.1 18.5 1M2L 44.2 44.2 41.1 45.4 45.5 0M3L 38.4 38.4 48.7 33.534.1 Fatty acid composition C8:0 14.4 14.3 10.5 10.8 11.0 C10:0 4.8 4.63.4 11.1 11.2 C12:0 0.0 0.0 0.0 1.0 0.0 C14:0 0.0 0.0 0.0 0.8 0.0 C16:03.2 3.1 8.6 33.3 10.2 C18:0 1.6 2.0 3.3 3.3 1.6 C18:1 49.2 49.4 20.731.6 23.3 C18:2 17.9 17.9 46.2 7.9 42.7 C18:3 8.9 8.7 7.1 0.0 0.0 others0.0 0.0 0.2 0.2 0.0 Note) M; medium-chain fatty acid, L; long-chainfatty acid, tr. = trace, for example C 8:0 means that the carbon numderis 8 and the number of unsaturated bond (carbon-carbon double bond) is 0(likewise in Tables 2, 3 and 4)

TABLE 2 Analytical values of oil or fat compositions (% by mass) ExampleComposition 6 Composition 7 Composition 8 Triglyceride composition 3M0L0.1 tr. 4.8 2M1L 3.4 5.1 6.1 1M2L 25.6 31.9 35.1 0M3L 70.9 63.0 54.0Fatty acid composition C8: 0 5.0 7.2 10.9 C10: 0 1.8 2.4 3.0 C12: 0 0.00.0 0.0 C14: 0 0.0 0.0 0.0 C16: 0 3.5 3.6 8.1 C18: 0 2.1 1.8 3.8 C18: 156.2 55.1 20.0 C18: 2 20.9 19.8 46.9 C18: 3 10.2 10.1 7.2 others 0.3 0.00.1

TABLE 3 Analytical values of oil or fat compositions (% by mass)Comparative example Composition 9 Composition 10 Triglyceridecomposition 3M0L 2.8 tr. 2M1L 21.0 0.5 1M2L 45.5 11.7 0M3L 30.7 87.8Fatty acid composition C8: 0 18.5 2.1 C10: 0 5.9 1.0 C12: 0 0.0 0.0 C14:0 0.0 0.0 C16: 0 3.1 3.7 C18: 0 1.5 2.1 C18: 1 45.9 58.5 C18: 2 16.721.7 C18: 3 8.4 10.6 others 0.0 0.3

TABLE 4 Analytical values of oil or fat compositions (% by mass) ControlSoybean oil Rapeseed oil Mixed oil Triglyceride composition 3M0L 0 020.0 2M1L 0 0 — 1M2L 0 0 — 0M3L 100 100 80.0 Fatty acid composition C8:0 0.0 0.0 15.1 C10: 0 0.0 0.0 4.9 C12: 0 0.0 0.0 0.0 C14: 0 0.0 0.0 0.0C16: 0 10.5 3.8 3.1 C18: 0 3.8 2.2 1.8 C18: 1 23.6 60.3 48.0 C18: 2 54.222.4 17.9 C18: 3 7.6 10.9 8.9 others 0.3 0.4 0.3

EXAMPLE 8

A feed having added thereto soybean oil (made by THE NISSHIN OIL MILLS,LTD.)(control)(the triglyceride composition and the fatty acidcomposition are shown in Table 4) or Composition 1, 6, 7, 9 or 10 in anamount of 25% by mass, was left to be ingested freely for 8 weeks by4-week-old Wistar strain male rats. The composition of the feed is shownin Table 5. For preventing the lack of essential fatty acids, thesoybean oil was added to each feed in an amount of 3% by mass. Asvitamins and minerals, those recommended by the American NutrientSociety were used, and their addition amounts to the feed were adjustedby energy density. Eight weeks after the administration of theexperimental feeds, 8 animals from each group were dissected, and themass of the visceral fat was measured. Further, for measuring the massof the subcutaneous fat, each cadaver was freeze-dried and measured forthe fat content using a Soxhlet's extractor. The results about the ratshaving been feeded for 8 weeks are shown in Table 6. Statisticallysignificant difference was not observed among all the test groups in themass of ingested feed, final body weight and tail length. The visceralfat mass and subcutaneous fat mass of the rats having been feeded for 8weeks were statistically low values in the groups of Compositions 1, 6and 7. It was revealed from the results of the animal test that whenComposition 1, 6 or 7 of the invention, wherein the proportion ofmiddle-chain fatty acids in all the fatty acids composing the oil or fatcomposition, and the proportion of triglycerides having two middle-chainfatty acid residues in the molecule in all the triglycerides fall in therange of the invention, was used, body fat accumulation was lower,compared with the case where the control oil or comparative Composition9 or 10 was used.

TABLE 5 Feed composition Composition % Oil or fat composition 25.0 Cornstarch 25.1 Casein 25.4 Sucrose 10.0 Soybean oil 3.0 Cellulose 5.0Mineral mixture 4.5 Vitamin mixture 1.3 L-cystine 0.38 Cholinebitartrate 0.32

TABLE 6 Results of animal experiment (8 weeks feeding) Soybean oilComposition Composition Composition Composition Composition (control) 16 7 9 10 Ingested feed 694 ± 7  688 ± 9 698 ± 7 691 ± 5 690 ± 6  699 ±7  mass (g/8 weeks) Final body 294 ± 5  285 ± 4 286 ± 5 285 ± 5 289 ± 6 290 ± 6  weight (g) Tail length 18 ± 1  18 ± 1  19 ± 1  18 ± 1 18 ± 1 18± 1 (cm) Visceral fat 21 ± 2  17 ± 1*  17 ± 1*  18 ± 1* 19 ± 2 21 ± 1mass (g) Subcutaneous 30 ± 2  25 ± 1*  26 ± 1*  26 ± 1* 29 ± 2 28 ± 1fat mass (g) Note) Data are shown in average value ± standard deviation.Symbol*; There is significant difference at a 5% or less level ofsignificance compared with the control.

EXAMPLE 9

A cooking test and a cold resistant test were carried out using oil orfat compositions. As to the cooking test, smoking, foaming, sputteringof the oil and flavor of the cooked product were evaluated. As to thecold resistant test, the appearance at the time of storage at a lowtemperature was observed. As oil or fat composition samples were used 7ones, namely rapeseed oil (made by THE NISSHIN OIL MILLS,LTD.)(control), Composition 1, Composition 2, Composition 4, Composition6, Composition 8 and an oil wherein rapeseed oil and MCT wherein thecomposing fatty acids are caprylic acid/capric acid=3/1 by mass ratiowere mixed at a mass ratio of 4:1 (mixed oil). The triglyceridecomposition and the fatty acid composition of the rapeseed oil and themixed oil are shown in Table 4.

The results of the cooking test are shown in Table 7. It was revealedfrom the results of the cooking test that Compositions 1, 2, 4, 6 and 8of the invention, wherein the proportion of medium-chain fatty acids inall the fatty acids composing the oil or fat composition, and theproportion of triglycerides having two medium-chain fatty acid residuesin the molecule in all the triglycerides fall in the range of theinvention, have cooking properties equal to those of the usual edibleoil. Further, Compositions 1, 2, 4 and 6, wherein the proportion oftriglycerides having three medium-chain fatty acid residues in themolecule in all the triglycerides composing the oil or fat compositionis 3% by mass or less, have high stability at the time of thedeep-frying cooking. Particularly, Composition 2 wherein the emulsifierswere incorporated was revealed to be excellent in antifoaming effect.Further, the same 7 samples were allowed to stand at 5° C. for 48 hoursand observed for appearance. The results are shown in Table 7. As aresult, in Composition 4, deposition of crystals was observed, but theother samples had transparent appearance.

TABLE 7 Results of the cooking test and the cold resistant test Rapeseedoil Composition Composition Composition Composition Composition(control) Mixed oil 1 2 4 6 8 Smoking 10 5 8 8 8 9 8 Foaming 10 1 8 10 89 8 Oil 10 5 9 9 9 9 9 sputtering Flavor 10 10 10 10 10 10 10 Deepfrying 10 1 8 9 8 8 6 stability Cold 10 8 8 8 5 8 8 resistance (5° C.)Note) Evaluation was made as follows using rapeseed oil as a control (10points); 10~7 points; usable, 6~4 points; there is a little problem foruse, 3~1 points; unusable.

-   Smoking: A Teflon-coated frypan of diameter 24 cm was heated in    advance for 30 seconds, 15 g of a sample oil was put therein and    heating was made for further 30 seconds. Then, foodstuffs for    vegetable frying were put in the frypan, the mixture was heated for    3 minutes, and proper amounts of salt and pepper were added. Smoking    at the time of the frying cooking was observed with the naked eye.-   Foamin, oil sputtering, flavor: A sample oil (600 g) was put in a    household electric fryer, 4 battered prawns were put therein, and    one minute later, the foaming and sputtering of the oil were    observed. Further, the flavor of the cooked prawns (tempura) was    evaluated.-   Stability in deep frying: A sample oil (600 g) was put in a    household electric fryer, battered prawns were deep-fried for 30    minutes, foodstuffs for croquettes were deep-fried for 30 minutes,    and finally chicken for frying without coating was deep-fried for 30    minutes, respectively at 180° C. Stability in deep frying cooking    was evaluated by the degree of occurrence of stable fine foam. Deep    frying was stopped when the occurrence of stable fine foam became    100% of the fryer surface area.-   Cold resistance: The appearance was observed at the time of storage    at a low temperature (allowed to stand at 5° C. for 48 hours).

1. An oil or fat composition at least 85% by mass of which aretriglycerides, wherein (a) the proportion of medium-chain fatty acids toall the fatty acids as constituents of the oil or fat composition isfrom 5 to 23% by mass, (b) the proportion of triglycerides having twomedium-chain fatty acid residues in the molecule to all thetriglycerides is from 1 to 20% by mass, and (c) the proportion oflong-chain saturated fatty acids to all of the long-chain fatty acids asconstituents of the oil or fat composition is at most 15% by mass, theoil or fat composition being obtained by transesterifying an edible oilor fat with a medium-chain fatty acid or a medium-chain fatty acidtriglyceride, the oil or fat composition not containing any of sucrosefatty acid esters, polyglycerol fatty acid esters, succinic acidmonoglycerides, sorbitol fatty acid esters and sorbitan fatty acidesters in a total amount of 0.1% by mass or more of the composition. 2.The oil or fat composition according to claim 1 wherein the medium-chainfatty acids are saturated fatty acids having 6 to 12 carbon atoms. 3.The oil or fat composition according to claim 2 wherein (d) theproportion of triglycerides having three medium-chain fatty acidresidues in the molecule to all the triglycerides is at most 3% by mass.4. A process for preparing an oil or fat composition which comprisesadding an emulsifier to the oil or fat composition according to claim 3.5. A process for preparing an oil or fat composition which comprisesadding an emulsifier to the oil or fat composition according to claim 2.6. The process according to claim 5 wherein the emulsifier is at leastone selected from sucrose fatty acid esters, polyglycerol fatty acidesters, succinic acid monoglycerides, sorbitol fatty acid esters andsorbitan fatty acid esters.
 7. The oil or fat composition according toclaim 1 wherein (d) the proportion of triglycerides having threemedium-chain fatty acid residues in the molecule to all thetriglycerides is at most 3% by mass.
 8. A process for preparing an oilor fat composition which comprises adding an emulsifier to the oil orfat composition according to claim
 7. 9. The process according to claim8 wherein the emulsifier is at least one selected from sucrose fattyacid esters, polyglycerol fatty acid esters, succinic acidmonoglycerides, sorbitol fatty acid esters and sorbitan fatty acidesters.
 10. An oil or fat composition for cooking comprising the oil orfat composition according to any one of claims 1 to 3 and at least oneadditive selected from vitamin E, an ascorbic acid fatty acid ester,lignan, coenzyme Q, a phospholipid and an oryzanol.
 11. A process forpreparing an oil or fat composition which comprises adding an emulsifierto the oil or fat composition according to claim
 1. 12. The processaccording to claim 11 wherein the emulsifier is at least one selectedfrom sucrose fatty acid esters, polyglycerol fatty acid esters, succinicacid monoglycerides, sorbitol fatty acid esters and sorbitan fatty acidesters.